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Do you think the COVID-19 pandemic lockdown will slow or possibly reverse the effects of climate change (due to decreased air travel, cars, fossil fuels being emitted)?
Simon Kingham, University of Canterbury
The COVID-19 lockdown has affected the environment in a number of ways.
The first is a reduction in air travel and associated emissions. Globally, air travel accounts for around 12% of the transport sector’s greenhouse gas emissions and this was predicted to rise. An ongoing reduction in air travel would lead to lower greenhouse gas emissions.
The lockdown has also meant less travel by road, which has resulted in measurably lower vehicle emissions and cleaner air in New Zealand.
Worldwide, daily emissions of carbon dioxide had dropped by 17% by early April (compared with 2019 levels) and just under half of the reduction came from changes in land transport. The same study estimated the pandemic could reduce global emissions by between 4% (if the world returns to pre-pandemic conditions mid-year) and 7% (if restrictions remain in place until the end of 2020).
But even a 7% drop would mean emissions for 2020 will roughly be the same as in 2011. The long-term impact of the pandemic on climate change depends on the actions governments take as economies recover – they will influence the path of global carbon dioxide emissions for decades.
Choosing how you travel
In New Zealand, the biggest reduction in emissions came from people not travelling as much, or at all. But as the lockdown lifted, these improvements seemed to be short term, with traffic volumes and the associated pollution now back at pre-COVID-19 levels.
There is significant uncertainty about all of the changes prompted by the pandemic lockdown, but international air travel is predicted to remain down in the short to medium term as the risk of inter-country transfer of COVID-19 remains high. For how long depends on the ability of other countries to effectively manage the virus or the availability of a vaccine.
Land transport is more within our control in New Zealand. How, and how much, we choose to travel will determine our greenhouse gas emissions. While many people are returning to their cars, there are some lockdown changes that could lead to longer-term emissions reductions.
Firstly, people now realise it is possible to work from home and may want to continue doing so in the future.
Keeping some lockdown changes
In many parts of the world, governments are implementing plans to lock in some of the reductions in traffic caused by the pandemic.
There are also initiatives to decarbonise the car fleet by replacing fossil fuelled vehicles with electric ones. In New Zealand, electric vehicles are exempt from road user charges and the government is investigating ways to increase the uptake of alternative fuels in the road freight industry.
These measures are important and reduce greenhouse gas emissions, but they are not designed to reduce the number of people travelling, or the mode they use. Congestion is an ongoing issue in Auckland and is now estimated to cost more than NZ$1 billion per year.
Another challenge is the growing rate of obesity, with one in three New Zealanders now obese. This is at least partly a transport-related challenge. We know obesity rates are higher in places where more people travel by car. Increased use of public transport can reduce obesity – as well as making people happier.
How long-lasting the COVID-19 impact on emissions is depends on how much we want some of the temporary changes to continue. For example, COVID-19 showed more people walk and cycle if there are fewer cars, which supports evidence that safety is a big barrier to cycling and we need dedicated cycle ways to keep people away from traffic. We also know people are happy with a little inconvenience to have safer play-friendly streets.
Encouraging some of the lockdown behavioural changes could have additional benefits and reduce greenhouse gas emissions at the same time.